Traditional historical analysis and personal recollections are paired with otherworldly footage from underwater cameraman Richard Stevenson and his team

Underwater cameraman Richard Stevenson and a colleague explore the wrecks of U-boats lying off the north-west coast of Ireland. Photo: BBC NI/Alleycats TV

Underwater cameraman Richard Stevenson and a colleague explore the wrecks of U-boats lying off the north-west coast of Ireland. Photo: BBC NI/Alleycats TV

Strewn along the ocean floor around the north-west coast of Ireland is the greatest collection of shipwrecks to be found anywhere in the world.

These include the barnacled skeletons of the lethal German U-boats that wreaked havoc on Britain’s North Atlantic convoys during the Second World War.